I have my in - line filter after the fuel pump and before the carb.
I really wondered why you would see any bubbles at all. It doesn't like, blow bubbles or anything like that . It just has a bubble in there after you start it, then it dissipates to a very small bubble while running. After it has " acted up " and I'am sitting on the shoulder of the road, I have popped the hood and found the old Clear View filter was EMPTY . It may be the fuel pump. Seems unlikely to me,
after it has " acted up ". sometimes it will have a shot or two of gas get thru , just enough to give you hope that it healed itself
only to shut down again. After it sits awhile it will have gas reappear in the filter and start again. I thought it may be "vapor lock", but it didn't have any issues like this before . I haven't changed any of the fuel line routing . Puzzling .
I have noticed, when I still had the Mr.Gasket clear view in-line filter installed, the fuel filter would be full when shut off or nearly full with maybe a small air bubble in view. I would check it in the morning and sometimes it would be full ,
other times you could actually see it emptying back into the fuel pump.
I'll throw a new stock pump on in the morning and see if that was it , keep you posted.